Nutritional assessment Flashcards
Albumin
35-50 g/L
Hb
< 120 g/L
<140 g/L
hematocrit (%)
< 37 % women, 40% men
glucose
3.9-6.1 mmol/L ( ~4-7mmol/L)
Nitrogen balance equation
( protein intake g / 6.25 ) - ( UUN +4 )
UUN in mmol= (UUN) x volume (L)
UNNmmol x ( 0.028g )
BMI
kg/ m^2
normal BMI
18.5 - 25
% weight change
( UBW- current)/ UBW x 100
- at risk if >5% in 1 mo, >10 % in 6 mo
to assess somatic protein levels?
N balance, creatine levels
4 major visceral proteins
albumin ( 17-21 days), transferritin ( 8-10 days), pre-albumin (2-4 days), RBP ( 10-12 hours)
albumin may be increased due to
dehydration ( diarrhea, vommiting )
albumin may be lowered not just due to inadequate protein but also
neg-acute protein, trauma, liver damage, over hydration, Mal- absorption, aging, edema
when would RBP and TTR be elevated? why?
renal disease, bc they are filtered and metabolized in the kidney
TTR also high in
hodgkins disease
RBP lowered also during?
liver disease, vit A def, zinc def, hyperthyroidism ( same as TTR)
transferrin high during
pregnancy, iron def
order of depletion for iron status
iron stores, transport iron, essential iron
lab tests for anemia
Hb
- if low further tests
serum ferritin ( would be low with low stores)
serum iron ( would also be low with deficiency )
total iron-binding capacity ( TIBC) –> need this to calculate transferrin saturation. if this is high it is indicative of iron def
transferrin saturation: would be lowered ( < 30% def)
erythrocyte protoporphyrin: severe iron def, protoporphyrin will replace Hb, so this would increase in late stages of iron def
- main markers are the first 3 ( hb, ferritin, TIBC)
waist circumference
if >120 W, >140 M, increased risk of CVD and diabetes independent of BMI
lab tests fro folate deficiency anemia
serum folate - to detect first
RBC folate - would indicate more severe folate def
why is Hb not a good indicator of iron deficiency?
as shown in the graphs, it’s decline is not seen until after Fe depletion. In comparison, ferritin stores decline earlier on and before depletion occurs. in this sense, if one measured serum ferritin - iron def could be caught much earlier
risk factors for poor iron status
vegetarian low vitamin C low fortified foods fequent teas and coffee with meals iron inhibitors with meals ( phytates, tannins, oxalates- plant anti-nutrients - beans, grains, nuts, seeds) ASA use menorrhagia 3 + annual blood donations pregnancy
iron supplementation should be what?
ferrous sulfate
- ferrous = 3x better absorption
rise 1 g/L of Hb per week
- take on empty stomach with liquid
Clinical assessment
patients medical, social, psychological history
- physical examination for clinical signs of symptoms
TEE includes
REE or BMR (65-70%)
PA (20-30%)
TEF (10%)
injury/stress
TEE = ?
REE x Activity factor x stress factor
or institute of medicine equations:
women: TEE= 387 - (7.31 x age) + PA x (10.9 x weight (kg) + 660.7 x height (m))
Harris - Benedict (1919) limitations
- tends to overestimate by 5-15%
- can’t use in obese indiviuals
when do we use ideal weight?
if patient is obese > 30 BMI and non-hospitalized
- except for Mifflin- St jeor
to find TEE first must find?
REE with an estimate of one of the 4 main equations, or indirect calorimeter
in Mifflin- st Joer equation what is important?
to always use current body weight
- better predicts REE in non- obese and obese subjects
REE is used interchangeably to?
BMR, BEE ( for purées of this course)
REE is directly proportional to ??
lean body mass
- in Harris- Benedict equation this is based on the fact that men have more LBM and with age, LBM decreases
which equation is not appropriate for obese patients and tend to overestimate by 5-10%
H-B equation
FAO/WHO
only factors in weight and categorized by age and sex
- tend to be less precise due to simplicity
Mifflin-st Jeor
less overestimation than H-B
- in general more appropriate for obese individuals
- but in extremely obese not as much bc more weight is due to more fat and not more LBM ( however yes, obese ppl have more LBM than thin, but at the extreme side, more fat )
- important o use CURRENT body weight in this one, even if above 30. ( unless over BMI of 35, than use BMI to 30
- PAL and stress factor must be included
Rule of thumb
25-35 kcal/kg body weight for non-obese ppl
in Mifflin if patient has BMI of 32 do you use current or ideal BW?
current, only if above 35 do change to 30
PAL
multiply the REE by PAL
- this combines both normal movements and sports/exercise
the institute of medicine has what that is different?
physical activity factor
- in the previous ones it was PAL but this equation has PA factor
in summary of equations
we have two options: use equation to estimate REE x by PAL x stress factor OR use IOM equation which incorporates everything ( using a PA instead) and does not have a stress factor ( bc it is for healthy ppl )
- using for hospitalized patients and x-ing by stress factor is actually an overestimate
healthy adults protein
1.0 g/kg/day
elderly adults PRO
1.0-1.2 g/kg/day
over hydration most severe issue/concern
hyponatremia
fluid balance
urine output + 500mL/day
do fluid req change in various states of disease
yes
list symptoms of dehydration ( not common ones )
trachycardia
lowered BT
rapid weight loss (1kg= 470ml)
increase in albumin, Na, creatine, Hb, Hct
over hydration symptoms
increased BP edema slow pulse decrease Na, K, Albumin, creatine, Hb, Hct rapid weight gain
things to consider for elderly as bod changes
lowered LBM low appetite - reduced energy need higher protein decrease Ca absorbance vit D less effacent synthesis decrease sense of thirst
prevalence of malnutrition
15% - community
15-80% - hospitals
80% in long term care
tool for screening malnutrition that is canid, reliable, sensitive, specific?
doesn’t exist
elements of screening?
current condition- BMI
stable condition- ( involuntary weight loss?)
will condition deteriorate? - what is food intake
impact of disease on deterioration
what is only valid instrument?
NRS 2002 - (nutrition screening risk 2002)
